xref: /OK3568_Linux_fs/kernel/arch/arm/lib/io-readsb.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun/*
3*4882a593Smuzhiyun *  linux/arch/arm/lib/io-readsb.S
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun *  Copyright (C) 1995-2000 Russell King
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun#include <linux/linkage.h>
8*4882a593Smuzhiyun#include <asm/assembler.h>
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun.Linsb_align:	rsb	ip, ip, #4
11*4882a593Smuzhiyun		cmp	ip, r2
12*4882a593Smuzhiyun		movgt	ip, r2
13*4882a593Smuzhiyun		cmp	ip, #2
14*4882a593Smuzhiyun		ldrb	r3, [r0]
15*4882a593Smuzhiyun		strb	r3, [r1], #1
16*4882a593Smuzhiyun		ldrbge	r3, [r0]
17*4882a593Smuzhiyun		strbge	r3, [r1], #1
18*4882a593Smuzhiyun		ldrbgt	r3, [r0]
19*4882a593Smuzhiyun		strbgt	r3, [r1], #1
20*4882a593Smuzhiyun		subs	r2, r2, ip
21*4882a593Smuzhiyun		bne	.Linsb_aligned
22*4882a593Smuzhiyun
23*4882a593SmuzhiyunENTRY(__raw_readsb)
24*4882a593Smuzhiyun		teq	r2, #0		@ do we have to check for the zero len?
25*4882a593Smuzhiyun		reteq	lr
26*4882a593Smuzhiyun		ands	ip, r1, #3
27*4882a593Smuzhiyun		bne	.Linsb_align
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun.Linsb_aligned:	stmfd	sp!, {r4 - r6, lr}
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun		subs	r2, r2, #16
32*4882a593Smuzhiyun		bmi	.Linsb_no_16
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun.Linsb_16_lp:	ldrb	r3, [r0]
35*4882a593Smuzhiyun		ldrb	r4, [r0]
36*4882a593Smuzhiyun		ldrb	r5, [r0]
37*4882a593Smuzhiyun		mov	r3, r3,     put_byte_0
38*4882a593Smuzhiyun		ldrb	r6, [r0]
39*4882a593Smuzhiyun		orr	r3, r3, r4, put_byte_1
40*4882a593Smuzhiyun		ldrb	r4, [r0]
41*4882a593Smuzhiyun		orr	r3, r3, r5, put_byte_2
42*4882a593Smuzhiyun		ldrb	r5, [r0]
43*4882a593Smuzhiyun		orr	r3, r3, r6, put_byte_3
44*4882a593Smuzhiyun		ldrb	r6, [r0]
45*4882a593Smuzhiyun		mov	r4, r4,     put_byte_0
46*4882a593Smuzhiyun		ldrb	ip, [r0]
47*4882a593Smuzhiyun		orr	r4, r4, r5, put_byte_1
48*4882a593Smuzhiyun		ldrb	r5, [r0]
49*4882a593Smuzhiyun		orr	r4, r4, r6, put_byte_2
50*4882a593Smuzhiyun		ldrb	r6, [r0]
51*4882a593Smuzhiyun		orr	r4, r4, ip, put_byte_3
52*4882a593Smuzhiyun		ldrb	ip, [r0]
53*4882a593Smuzhiyun		mov	r5, r5,     put_byte_0
54*4882a593Smuzhiyun		ldrb	lr, [r0]
55*4882a593Smuzhiyun		orr	r5, r5, r6, put_byte_1
56*4882a593Smuzhiyun		ldrb	r6, [r0]
57*4882a593Smuzhiyun		orr	r5, r5, ip, put_byte_2
58*4882a593Smuzhiyun		ldrb	ip, [r0]
59*4882a593Smuzhiyun		orr	r5, r5, lr, put_byte_3
60*4882a593Smuzhiyun		ldrb	lr, [r0]
61*4882a593Smuzhiyun		mov	r6, r6,     put_byte_0
62*4882a593Smuzhiyun		orr	r6, r6, ip, put_byte_1
63*4882a593Smuzhiyun		ldrb	ip, [r0]
64*4882a593Smuzhiyun		orr	r6, r6, lr, put_byte_2
65*4882a593Smuzhiyun		orr	r6, r6, ip, put_byte_3
66*4882a593Smuzhiyun		stmia	r1!, {r3 - r6}
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun		subs	r2, r2, #16
69*4882a593Smuzhiyun		bpl	.Linsb_16_lp
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun		tst	r2, #15
72*4882a593Smuzhiyun		ldmfdeq	sp!, {r4 - r6, pc}
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun.Linsb_no_16:	tst	r2, #8
75*4882a593Smuzhiyun		beq	.Linsb_no_8
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun		ldrb	r3, [r0]
78*4882a593Smuzhiyun		ldrb	r4, [r0]
79*4882a593Smuzhiyun		ldrb	r5, [r0]
80*4882a593Smuzhiyun		mov	r3, r3,     put_byte_0
81*4882a593Smuzhiyun		ldrb	r6, [r0]
82*4882a593Smuzhiyun		orr	r3, r3, r4, put_byte_1
83*4882a593Smuzhiyun		ldrb	r4, [r0]
84*4882a593Smuzhiyun		orr	r3, r3, r5, put_byte_2
85*4882a593Smuzhiyun		ldrb	r5, [r0]
86*4882a593Smuzhiyun		orr	r3, r3, r6, put_byte_3
87*4882a593Smuzhiyun		ldrb	r6, [r0]
88*4882a593Smuzhiyun		mov	r4, r4,     put_byte_0
89*4882a593Smuzhiyun		ldrb	ip, [r0]
90*4882a593Smuzhiyun		orr	r4, r4, r5, put_byte_1
91*4882a593Smuzhiyun		orr	r4, r4, r6, put_byte_2
92*4882a593Smuzhiyun		orr	r4, r4, ip, put_byte_3
93*4882a593Smuzhiyun		stmia	r1!, {r3, r4}
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun.Linsb_no_8:	tst	r2, #4
96*4882a593Smuzhiyun		beq	.Linsb_no_4
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun		ldrb	r3, [r0]
99*4882a593Smuzhiyun		ldrb	r4, [r0]
100*4882a593Smuzhiyun		ldrb	r5, [r0]
101*4882a593Smuzhiyun		ldrb	r6, [r0]
102*4882a593Smuzhiyun		mov	r3, r3,     put_byte_0
103*4882a593Smuzhiyun		orr	r3, r3, r4, put_byte_1
104*4882a593Smuzhiyun		orr	r3, r3, r5, put_byte_2
105*4882a593Smuzhiyun		orr	r3, r3, r6, put_byte_3
106*4882a593Smuzhiyun		str	r3, [r1], #4
107*4882a593Smuzhiyun
108*4882a593Smuzhiyun.Linsb_no_4:	ands	r2, r2, #3
109*4882a593Smuzhiyun		ldmfdeq	sp!, {r4 - r6, pc}
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun		cmp	r2, #2
112*4882a593Smuzhiyun		ldrb	r3, [r0]
113*4882a593Smuzhiyun		strb	r3, [r1], #1
114*4882a593Smuzhiyun		ldrbge	r3, [r0]
115*4882a593Smuzhiyun		strbge	r3, [r1], #1
116*4882a593Smuzhiyun		ldrbgt	r3, [r0]
117*4882a593Smuzhiyun		strbgt	r3, [r1]
118*4882a593Smuzhiyun
119*4882a593Smuzhiyun		ldmfd	sp!, {r4 - r6, pc}
120*4882a593SmuzhiyunENDPROC(__raw_readsb)
121